So is it safe to get one of these unlocked international phones? They claim the phone supports the following...does T-Mobile support any of these:
GSM850, GSM900, GSM1800, GSM1900, UMTS800 (B6), UMTS850 (B5), UMTS900 (B8), UMTS1900 (B2), UMTS2100 (B1), UMTS800 (B19), LTE2100 (B1), LTE850 (B5), LTE1800 (B3), LTE2600 (B7), LTE1900 (B2), LTE800 (B18), LTE900 (B8), LTE800 (B20), LTE800 (B26), TD-LTE2600 (B38), LTE800 (B19), TD-LTE2500 (B41), TD-LTE2300 (B40), TD-LTE1900 (B39), LTE700 (B28). Secondary Cellular Networks: GSM850, GSM900, GSM1800, GSM1900
A couple, you would get 2G for sure but then for HSPA 3G/3.5G (aka 4G non-LTE) you would only get those in a few markets as T-Mobile's primary band in most markets is Band 4 (1700/2100). Not to mention you probably won't find any "international" versions that have T-Mobile's low band LTE frequency which is Band 12.
Here is a link that goes over all their frequencies; T-Mobile network bands & technologies
Manage your T-Mobile account